Nano-structures are suitable for use in a wide variety of applications, including applications for shock absorption, promoting adhesion, tuning surface wettability, and micro- or nano-fluidic filtration, among other applications. Nano-scale structures may be formed on a surface using a template formed on a surface, and then filling pores in the template with a select material. Once the pores are sufficiently filled, the template may be removed to expose nano-structures on and above the surface.